The story

Investigators trying to figure out what caused Wednesday's massive bridge collapse are focusing on the southern end of the span, which "behaved differently" as it fell, the National Transportation Safety Board said Friday.

The NTSB, which is investigating the disaster that killed at least five people and injured dozens, is also hoping another video provided by the Army Corps of Engineers will provide new images of the collapse.

What's getting investigators' attention is the way the southern part of the bridge fell in a video they've already examined -- recorded by a security camera near the bridge's north end -- and the way the section settled after the collapse. Read full article »